[cost] for TF 11

Author: zsdonghao

tensorlayer/cost.py

@@ -34,7 +34,7 @@ def cross_entropy(output, target, name=None):
     """
     assert name is not None, "Please give a unique name to tl.cost.cross_entropy"
 
-    if tf.__version__ <= "0.12":
+    if tf.__version__ <= "0.11":
         return tf.reduce_mean(tf.nn.sparse_softmax_cross_entropy_with_logits(logits=output, targets=target))
     else: # TF 1.0
         return tf.reduce_mean(tf.nn.sparse_softmax_cross_entropy_with_logits(labels=target, logits=output, name=name))